Interpretation Response #07-0225 ([Packaging Applications for Dangerous Goods, LLC] [Mr. David Gluntz])
Below is the interpretation response detail and a list of regulations sections applicable to this response.
Interpretation Response Details
Response Publish Date:
Company Name: Packaging Applications for Dangerous Goods, LLC
Individual Name: Mr. David Gluntz
Location State: OH Country: US
View the Interpretation Document
Response text:
February 25, 2008
Mr. David Gluntz
Packaging Applications for Dangerous Goods, LLC
3583 Blackbottom Court,
Columbus, OH 43221-4501
Ref. No. 07-0225
Dear Mr. Gluntz:
This responds to your November 28, 2007 email and subsequent telephone conversations requesting clarification of the general design requirements for DOT portable tanks under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask whether installing a "bleed off valve" assembly as a component of the pressure relief system for a DOT 51 portable tank is prohibited and requires a special permit to install.
Your enclosed sketch indicates the bleed off valve assembly would be installed between the pressure gauge/tell-tale indicator and the pressure relief device to allow for the safe removal of vapors trapped in the void space should a leak occur in the frangible disc.
It does not appear that the installation of the bleed off valve assembly involves a modification of the DOT 51 portable tank that would invalidate the ASME U stamp. Therefore, the bleed off valve assembly installed as a component of the pressure relief system as shown in your sketch is not prohibited and does not require a special permit to install. However, we highly recommend the use of good engineering practices (e.g., a leakage test) when installing the assembly. A report of the installment and any testing must be made a part of the records for the portable tank.
I hope this information is helpful. Please contact us if you require additional assistance.
Sincerely,
Hattie L. Mitchell
Chief, Regulatory Review and Reinvention.
Office of Hazardous Materials Standards
178.275(g)(3)